Dynamically Reconfigurable Fieldbus Communications Interface

Abstract

A dynamically reconfigurable fieldbus communications interface includes programmable logic which comprises a static area and at least one dynamic area; and control circuitry configured to program the at least one dynamic area using one of a plurality of interchangeable fieldbus stack hardware configurations, each conforming to a respective fieldbus protocol type.

What is claimed is: 
     
         1 . A dynamically reconfigurable fieldbus communications interface comprising:
 programmable logic that comprises a static area and at least one dynamic area; and   control circuitry configured to program the at least one dynamic area using one of a plurality of interchangeable fieldbus stack hardware configurations, each conforming to a respective fieldbus protocol type.   
     
     
         2 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 1 , wherein the at least one dynamic area is dynamically reconfigurable to operate according to a selected fieldbus protocol type without affecting the static area or any other dynamic area. 
     
     
         3 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 1 , wherein a size of the at least one dynamic area is determined to accommodate the largest of the interchangeable fieldbus stack hardware configurations. 
     
     
         4 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 1 , further comprising pin switches for the different fieldbus protocol types implemented within the at least one dynamic area. 
     
     
         5 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 1 , wherein the at least one dynamic area outputs only one set of fieldbus signals. 
     
     
         6 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 5 , wherein the control circuitry is configured to receive a reconfiguration command specifying a required fieldbus protocol type and, in response to receiving the reconfiguration command:
 to identify a target fieldbus instance to be exchanged based on the reconfiguration command;   to load a replacement fieldbus stack hardware configuration corresponding to the required fieldbus protocol type onto a dynamic area currently occupied by the target fieldbus instance;   to verify that loading of the replacement fieldbus stack hardware configuration successfully created a replacement fieldbus instance;   to establish communication between the replacement fieldbus instance and at least one field device.   
     
     
         7 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 1 , wherein the programmable logic comprises a plurality of dynamic areas including the at least one dynamic area, whereby the dynamically reconfigurable fieldbus communications interface is operable to host multiple fieldbus instances, each corresponding to a specific protocol type. 
     
     
         8 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 7 , wherein the plurality of dynamic areas are operable to implement separate interfaces for communicating with respective field devices of a process control system. 
     
     
         9 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 7 , wherein the plurality of dynamic areas host fieldbus instances conforming to the same fieldbus protocol type. 
     
     
         10 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 7 , wherein the plurality of dynamic areas host fieldbus instances conforming to different fieldbus protocol types. 
     
     
         11 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 1 , wherein the fieldbus stack hardware configuration that is used to program the at least one dynamic area is encrypted. 
     
     
         12 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 11 , wherein the fieldbus stack hardware configuration is encrypted using asymmetric cryptography, wherein the programmable logic is configured to generate a public-private key pair, wherein the public key of the pair is usable to encrypt a partial bit-stream file for the at least one dynamic area, and wherein a private key of the pair is stored in memory. 
     
     
         13 . The dynamically reconfigurable fieldbus communications interface as claimed in  claim 1 , wherein the control circuitry comprises control logic programmed into the programmable logic and/or a processor system configured to run control software. 
     
     
         14 . A method for dynamically reconfiguring a fieldbus communications interface which comprises programmable logic comprising a static area and at least one dynamic area, the method comprising programming the at least one dynamic area using one of a plurality of interchangeable fieldbus stack hardware configurations, each conforming to a respective fieldbus protocol type. 
     
     
         15 . A computer-readable medium comprising instructions which, when executed by a computing system, cause the computing system to perform a method for dynamically reconfiguring a fieldbus communications interface that comprises programmable logic comprising a static area and at least one dynamic area, the method comprising programming the at least one dynamic area using one of a plurality of interchangeable fieldbus stack hardware configurations, each conforming to a respective fieldbus protocol type.